Wireless communication apparatus, wireless communication network and software upgrading method

ABSTRACT

A base station control portion  200  selects one or plural signals from signals received by plural settable communication paths in accordance with the state of the wave. A wireless communication apparatus  110  communicates with a wireless terminal  300  and a wired communication network. When the wireless communication apparatus  110  receives a request for upgrading software from a network management device  250 , the wireless communication apparatus  110  controls the state of the transmission wave of a wireless interface so as to switch a communication path in which communication services are being provided to another wireless communication apparatus  110  without blackouts, rewrites the set software to software having been received through a wired interface in advance, returns the state of the transmission wave of the wireless interface and upgrades software without blackouts of the supply of communication services to the wireless terminal  300.

The present application is a continuation of application Ser. No.12/816,407, filed Jun. 16, 2010, now U.S. Pat. No. 7,937,079; which is acontinuation of application Ser. No. 12/250,702, filed Oct. 14, 2008,now U.S. Pat. No. 7,773,981; which is a continuation of application Ser.No. 10/636,806, filed Aug. 8, 2003, now U.S. Pat. No. 7,447,497, thecontents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a wireless communication apparatus, awireless communication network and a software upgrading method and, inparticular, to a wireless communication apparatus, a wirelesscommunication network and a software upgrading method for upgradingsoftware without the blackouts of communication services.

Wireless communication networks including wireless terminals andwireless communication apparatus have been introduced rapidly inaddition to conventional wired communication networks. In the fields ofwireless communication networks, Time Division Multiple Access (TDMA)communication networks for multiplying voice signals, for example, in atime division manner for communication have been adopted, and CodeDivision Multiple Access (CDMA) communication networks forcode-multiplying voice signals, for example, with a spread code will bewidely spread from now on. Thus, communications with any one can beperformed any time and anywhere. These kinds of communication networkscan operate by software included in each communication apparatus withina network and provide users of wireless terminals with various kinds ofcommunication services such as voice communication and datacommunication. Therefore, the software for the communication apparatusmust be upgraded properly every time the contents of each ofcommunication services provided by the communication network advances.

A wireless communication apparatus is used for a wireless communicationnetwork and is called base station. The wireless communication is aninterface apparatus for a wireless terminal and a communication network.The software as described above must be upgraded as required forproviding various kinds of communication services. Therefore, varioussoftware upgrading methods have been proposed (such as JP-A-10-63498 andU.S. Pat. No. 2,980,201 or JP-A-10-320210). Upgrading the software forproviding communication services is required in a general communicationnetwork. Therefore, software upgrading methods (such as JP-A-7-319683and JP-A-2001-56756) have been proposed which allows the upgrading ofsoftware during the communication system (communication network) is inuse without loss of reliability of the communication network (such asJP-A-7-319683 and JP-A-2001-56756).

Conventionally, a system for mutually connecting a wirelesscommunication network and another communication network has been knownfor implementing diversity and hand-over for selectively synthesizingsignals excellent in conversation quality based on the signal exchangedwith plural base stations (such as JP-A-2001-16227). In a CDMAcommunication network, a soft hand-over technology (such as “3G TR25.832V4.0.0”, issued by 3GPP, March 2001, Section 5.2.1) has been known forsynthesizing signals from communications with plural base stations andselecting a communication path when a base station is changed in orderto switch a communication path without blackouts.

In a general communication network, reliability is important in order toprevent a communication blackout. Therefore, a method for upgradingsoftware set in inactive hardware has been adopted by providing hardwarewith redundancy as disclosed in JP-A-7-319683 and JP-A-2001-56756, forexample. Thus, the software for providing communication services and forcontrolling operations of a communication network can be upgraded duringthe software is in use.

On the other hand, in a wireless communication network, communicationwith wireless terminals is performed within an area where radio wavesfrom a base station can reach. The area is called cellular. A cellularof several km radius is generally used. In other words, the number ofaccommodatable users and covered area are much smaller than those of aconventional wired communication network (or a switched network).Therefore, in order to provide communication services widely, many basestations must be provided widely. Thus, the cost efficiency of thecommunication network is significantly lost by providing these many basestations with redundancy like the wired communication network facilityas disclosed above. Furthermore, plural frequency bands and CDMA spreadcodes must be assigned. Thus, the limited resource is wasted, and thenumber of users is reduced, which also reduces the serviceability.Therefore, as disclosed in JP-A-10-63498 and U.S. Pat. No. 2,980,201 orJP-A-10-320210, for example, a method is generally known for selecting abase station in accordance with a proper rule and terminating acommunication service in the base station for upgrading software. Forexample, an operator selects a base station having lower traffic in atime zone such as at midnight and upgrades software by protectingimportant calls and placing the base station off-line.

However, the method will impose larger loads on the operator formanaging a wireless communication network in future, and the supply ofeconomical wireless communication networks and communication servicesmay be difficult. For example, a wireless communication network may bewidely spread and the number of terminals used by users may increase. Inthis case, these terminals are used while moving, and the traffic ofeach base station always changes without blackouts. Furthermore, acommunication network may be more used without recognizing timedifferences in a more global communication network, and the traffic maynot be always reduced at midnight in Japan. Therefore, the selection ofa base station having low traffic and the protection of important callsas described above may be difficult, and the loads on operators mayincrease. Furthermore, from users' point of view, the number ofcommunication service blackouts (or communication disconnection) due tosoftware upgrading may increase. Furthermore, the level of reliabilityand serviceability may decrease because the supply of new servicesdelays due to the delay of the software upgrading. Therefore, a wirelesscommunication apparatus, wireless communication network and method foroperating them (software upgrading method) are desired for upgradingsoftware of so-called on-line communication apparatus, which eliminatesthe blackouts of a communication service in use in a wirelesscommunication network including wireless communication apparatus (basestations) without redundancy and which can provide the latestcommunication services.

SUMMARY OF THE INVENTION

In view of these issues, it is an object of the invention to provide awireless communication apparatus, a wireless communication network and asoftware upgrading method, which can upgrade software in the wirelesscommunication apparatus within the wireless communication network evenwhile the wireless communicating network is providing variouscommunication services. It is another object of the invention to providea wireless communication apparatus, a wireless communication network anda software upgrading method, which can upgrade software withoutblackouts of communication services being provided. It is another objectof the invention that these apparatus and method can be achieved withsimple and economical constructions and steps.

According to the invention, in order to achieve these objects, a softhandover technology (as disclosed in “3G TR25.832 V4.0.0”, issued by3GPP, March 2001, Section 5.2.1”, for example) provided for a CDMAcommunication network is used to provide a wireless communicationapparatus and a wireless communication network and a method foroperating them. More specifically, in a CDMA communication network,communication paths are switched from one terminal to plural basestations. One having good quality of communication is selected from thebase stations and is used for communication actually with the otherparty. Thus, the state of the transmission wave of the base station inwhich software will be upgraded can be controlled. Then, thecommunication path providing communication services can be switched fromthe base station to another base station without blackouts such that astate where the base station no longer provides communication servicescan be obtained. Under this condition, the software is upgraded, and thestate of the transmission wave is returned to the original state afterthe software upgrading. The base station selection is repeated inaccordance with a predetermined rule such that software in base stationswithin a wireless communication network can be upgraded without theblackouts of communication services.

According to first aspect of the invention, there is provided a wirelesscommunication apparatus for communicating with a wireless terminal and awired communication network within a handover-possible wirelesscommunication network, the apparatus including a wireless interface forcommunicating with the wireless terminal, a wired interface forcommunicating the wired communication network, a communicationprocessing portion for performing processing for providing communicationservices to the wireless terminal through the wireless interface and thewired interface, and a control portion for controlling apparatus,wherein the control portion changes the state of the transmission waveof the wireless interface in accordance with a predetermined rule,upgrades set software to software having been received through the wiredinterface in advance, and returns the state of the transmission wave ofthe wireless interface after the software upgrading.

According to second aspect of the invention, there is provided ahandover-possible wireless communication network, the network includinga wireless communication apparatus for communicating with a wirelessterminal and a wired communication network, a control device having ahandover unit for selecting one or plural signals from signals receivedfrom plural settable communication paths in accordance with the wavestate and communicating with the wireless communication apparatus, and anetwork management device for managing a network, wherein the networkmanagement device creates a wireless communication apparatus group byselecting, in accordance with a predetermined rule, one or plural of thewireless communication apparatus in which software will be upgraded, andsends software to be upgraded and an upgrading request to the wirelesscommunication apparatus belonging to the created wireless communicationapparatus group, wherein the wireless communication apparatus receivesthe software and upgrading request having been sent from the networkmanagement device, changes the state of the transmission wave so as tomake the control device to switch the communication path in whichcommunication services are being provided to another wirelesscommunication apparatus without blackouts in accordance with thereceived upgrading request, upgrades set software to the receivedsoftware, and returns the state of the transmission wave after softwareupgrading.

According to third aspect of the invention, there is provided a softwareupgrading method for upgrading software in a wireless communicationapparatus in a wireless communication network having a wirelesscommunication apparatus for communicating with a wireless terminal and awired communication network, a control device having a handover unit forperforming handover and communicating with the wireless communicationapparatus, and a network management device for managing a network, themethod including the steps of selecting one or plural wirelesscommunication apparatus in which software will be upgraded in accordancewith a predetermined rule and creating a wireless communicationapparatus group by the network management device or the control device,sending software to be upgraded and an upgrading request to the wirelesscommunication apparatus belonging to the created wireless communicationapparatus group by the network management device or the control device,receiving the upgrading request and changing the state of thetransmission wave so as to switch the communication path in whichcommunication services are being provided to another wirelesscommunication apparatus without blackouts by the wireless communicationapparatus, upgrading set software to the received software by thewireless communication apparatus and returning the state of thetransmission wave after software upgrading by the wireless communicationapparatus.

According to forth aspect of the invention, there is provided ahandover-possible wireless communication network, the network includinga wireless communication apparatus having plural sectors, forcommunicating between a wireless terminal and a wired communicationnetwork, a control device having a handover unit for selecting one orplural signals from signals received from plural settable communicationpaths in accordance with the wave state and communicating with thewireless communication apparatus, and a network management device formanaging a network, wherein the network management device sends softwareto be upgraded and an upgrading request to one or plural wirelesscommunication apparatus in which software will be upgraded, wherein thewireless communication apparatus receives the software and upgradingrequest having been sent from the network management device,sequentially selects at least one sector of plural sectors and changesthe state of the transmission wave of the selected sector so as to makethe control device switch the communication path in which communicationservices are being provided to another wireless communication apparatuswithout blackouts in accordance with the received upgrading request,upgrades set software to the received software, and returns the state ofthe transmission wave after software upgrading.

According to fifth aspect of the invention, there is provided a softwareupgrading method for upgrading software in a wireless communicationapparatus in a wireless communication network having plural sectors, awireless communication apparatus for communicating with a wirelessterminal and a wired communication network, a control device having ahandover unit for performing handover and communicating with thewireless communication apparatus, and a network management device formanaging a network, the method including the steps of sending softwareto be upgraded and an upgrading request to one or plural wirelesscommunication apparatus in which software will be upgraded by thenetwork management device or the control device, receiving the upgradingrequest, sequentially selecting at least one sector of plural sectorsand changing the state of the transmission wave of the selected sectorso as to switch the communication path in which communication servicesare being provided to another wireless communication apparatus withoutblackouts by the wireless communication apparatus, upgrading setsoftware to the received software by the wireless communicationapparatus, and returning the state of the transmission wave aftersoftware upgrading by the wireless communication apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a construction and operational exampleof a wireless communication network;

FIG. 2 is a block diagram showing a construction example of a basestation;

FIG. 3 is a block diagram showing a construction example of a basestation control portion;

FIG. 4 is a block diagram showing a construction example of a networkmanagement device;

FIG. 5 is a block diagram showing a construction of a wirelesscommunication network and an operational example where a transmissionradio wave of a base station is reduced;

FIG. 6 is an operational explanatory diagram for describing an exampleof a software upgrading operation in a base station;

FIG. 7 is a flow diagram showing an example of an operation forselecting a base station where software will be upgraded;

FIG. 8 is an explanatory diagram for describing a base station selectingoperation;

FIG. 9 is another explanatory diagram for describing a base stationselecting operation;

FIG. 10 is another explanatory diagram for describing a base stationselecting operation;

FIG. 11 is another explanatory diagram for describing a base stationselecting operation;

FIG. 12 is another explanatory diagram for describing a base stationselecting operation;

FIG. 13 is an operational explanatory diagram showing an operationalexample of a base station for upgrading software;

FIG. 14 is a block diagram showing a construction and operationalexample of a wireless communication network in which one base stationhas plural sectors;

FIG. 15 is a block diagram showing a construction example of a basestation having plural sectors;

FIG. 16 is a block diagram showing a construction of a wirelesscommunication network in which one base station has plural sectors andshowing another operational example;

FIG. 17 is an operational explanatory diagram for describing an exampleof a software upgrading operation in a base station;

FIG. 18 is an operational explanatory diagram showing a partial detailof an operational example for upgrading software in a base station;

FIG. 19 is an operational explanatory diagram showing an operationalexample of a sector control portion within a base station for upgradingsoftware; and

FIG. 20 is an operational explanatory diagram showing an operationalexample of an apparatus control portion within a base station in whichsoftware is upgraded.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Constructions of a wireless communication apparatus and wirelesscommunication network and a software upgrading method according to thisembodiment will be described in detail below with reference to drawings.

FIG. 1 is a block diagram showing a construction example of a wirelesscommunication network according to this embodiment. A wirelesscommunication network 10 implements communication between terminals byhaving a construction mentioned below.

Plural mobile terminals MS1 300-1 and MS2 300-2 and plural wirelesscommunication apparatus (called base station hereinafter) BS1 110-1 toBS8 110-8 are connected by a wireless communication path, not shown.More specifically, each base station BS has a radio wave reachable areacalled cellular. Here, cellulars 100-1 to 100-8 are shown. Each basestation BS performs wireless communication by using a terminal MS andCDMA, for example. Though not shown, the cellulars of base stationsoverlap with each other, and for example, communication paths 900-2 and910-2 through plural base stations BS1 110-1 and BS2 110-2 can be setfrom the terminal MS1 300-1. In the description for this embodiment, anarea where these plural base stations BS1 110-1 to BS8 110-8 cancommunication with the terminal MS is called mobile communicationnetwork 400.

The base stations BS-1 110-1 to BS8 110-8 of the mobile communicationnetwork 400-1 are connected with a base station control portion (controldevice) 200-1 through a main signal communication path 500-1. The basestation control portion 200 includes a diversity handover unit DHT 210for performing soft handover determined by “3GPP TR25.832 Section 5.2.1,for example, as described in detail later. The base station controlportion 200 selects one communication path having good communicationquality from plural communication paths 900 and 910 for communication.

When the destination of the communication from the terminal MS1 300-1 isin the same mobile communication network 400-1, the base station controlportion 200-1 returns a signal 930 selected by the DHT 210 to one of thebase stations BS1 110-1 to BS8 110-8 controlled by the base stationcontrol portion 200-1 and communicates with the destination terminal MS.On the other hand, when the destination is in another mobilecommunication network 400-2 (details of which is substantially the sameas those of the mobile communication network 400-1 and will not bedescribed herein), the base station control portion 200-1 exchangessignals 930-2 by using the base station control portion 200-2 and themobile communication network 400-2 through a communication network 150for connecting the base station control portions 200. Thus, the basestation control portion 200-1 can communicate with the destinationterminal. The communication network 150 may be any one of a publicnetwork, an exclusive line network and a private network. The mobilecommunication network 400-2 may be a so-called fixed network including awired communication network and terminals fixed in the wiredcommunication network.

The network management device 250 is connected with the base station BS110 and the base station control portions 200 in the communicationnetwork 10 through a control signal communication path 600. The controlsignal communication path 600 exchanges control signals for operationsadministration maintenance and provisioning (OAM & P). For example, thenetwork management device 250 manages and controls the entire facilityof the communication network 10 by upgrading software in the basestation 110. The number of base station BS 110, base station controlportion 200 and network managing device 250 is not limited to the numbershown in FIG. 1 but may be any number.

FIG. 2 is a block diagram showing a construction example of a basestation in a communication network. The base station 110 has aconstruction mentioned below. The base station connects betweenterminals and the base station control portion and communicates with thenetwork managing device.

When the base station 110 receives, at an antenna 119, a signal (wavesignal) from the terminal MS 300 through a wireless communication path,not shown, a wireless interface (IF) unit 116 performs terminationprocessing such as the conversion of the wave signal to an electricsignal. A communication processing unit 117 performs processing (such ascommunication processing for call controls) on the signal after thetermination processing in order to perform various communicationservices. A line interface (IF) unit 118 matches the interface with thebase station control portion 200. Then, the signal is sent to the basestation control portion 200 through a main signal communication path500. The base station 110 sends the signal from the base station controlportion 200 to the terminal MS 300 by following steps in the oppositedirection of the above-described processing.

The CPU 111 of the base station 110 controls the entire base station 110by using a control program stored in the memory 112 and data (such asinformation on terminals) required for operating the wirelesscommunication network 10. In this case, the data is stored in a storagedevice 113. These units are connected through an internal bus 115. AnI/O 114 connected to the internal bus 115 is an interface with thenetwork managing device 250 and exchanges, through a control signalcommunication path 600, a control signal (or command signal) and variouskinds of data required for control of the operation and maintenance ofthe communication network 10. Here, the I/O 114 may be removed and themain signal communication path 500 may be used to add these controlsignal and data to the signals exchanged through the main signalcommunication path 500. Then, the resulting signals may be exchangedthrough a line IF unit 118.

Upon the upgrading of communication services provided in the wirelesscommunication network 10, the CPU 111 of the base station 110 upgradessoftware (such as a control program) stored in the memory 112 orfirmware (such as a control program) stored in the wireless IF unit 116,communication processing unit 117 and line IF unit 118 by followingsteps and performing operations mentioned below and by keeping the basestation in use (in operation or at on-line state). The operation forupgrading software and/or firmware while the base station is being usedmay be called on-line upgrading hereinafter.

FIG. 3 is a block diagram showing a construction example of the basestation control portion. The base station control portion 200 has aconstruction mentioned below. The base station control portion 200connects a communication network 150 for connecting base station controlportions 200 and a base station and controls the base station 110.

The base station control portion 200 implements the communication of thebase stations by connecting plural line IF units 206-1 to 206-n, pluralline IF units 208-1 to 208-m and plural diversity handover units DHT210-1 and 210-2 through a switch 207. In this case, the plural line IFunits 206-1 to 206-n are interfaces with the base stations 110. Theplural line IF unit 208-1 to 208-m are interfaces with the communicationnetwork 150 (see FIG. 1). The plural diversity handover units DHT 210-1and 210-2 perform soft handover processing provided by the 3GPPstandard, for example (see “3G TR25.832 V4.0.0”, issued by 3GPP, March2001, Section 5.2.1, for example). The numbers of the line IF unit 208and the DHT 210 depend on the size of the communication network and maybe single.

The CPU 201 of the base station control portion 200 controls the entirebase station control portions 200 and the base stations 110 connected tothe base station control portions 200 by using a control program storedin the memory 202 and data (such as information on terminals and basestations) required for operations of the wireless communication network10 and stored in the storage device 203. These units are connectedthrough an internal bus 205.

The memory 202 or storage device 203 temporally stores programs (insoftware or firmware) required for the on-line upgrading in the basestations 110. The I/O 204 connected to the internal bus 205 is aninterface with a network managing device 250 and exchanges, through thecontrol signal communication path 600, control signals (such as commandsignals) and/or various kinds of data required for the control over theoperations and maintenance of the wireless communication network 10. TheI/O 204 may be removed and the main signal communication path 500, forexample, may be used. In this case, these control signals and data areadded to signals exchanged through the main signal control path 500 andmay be exchanged through the circuit IF unit 206 or 208.

Next, the handover will be described. According to this embodiment, thebase station control portion 200 implements soft handover processingprovided by the 3GPP standard (see “3G TR25.832 V4.0.0”, issued by 3GPP,March 2001, Section 5.2.1), for example. The specific operation will bedescribed with reference to FIGS. 1 to 3. Here, the DHT 210 mayimplement diversity handover (soft handover) by using the constructionand method disclosed in JP-A-2001-16227 (the DHT 210 may correspond to aDH 30 in drawings in the publication). The publication discloses aconstruction and method for ATM but the same construction and method canbe used for non-ATM signals. Therefore, the wireless communicationapparatus and wireless communication network according to the inventionare not limited to those for ATM signals.

Signals from the terminal MS1 300-1 reaches the base station controlportion 200 through at least two base stations. For example, in FIG. 1,a signal reaches the base station control portion 200-1 through thecommunication paths 900-2 and 910-2. The base station control portion200 inputs at least two signals received at the line IF 206 to the sameDHT 210-1 or 210-2 through the switch 207.

The DHT 210 selects one of the received signal from the wirelesscommunication path having a better wave condition based on theinformation on the state of the wireless communication path included inthe input, at least two signals. For example, the DHT 210 selects asignal from the communication path 910-2 having a better wave conditionfrom the signals received through the communication paths 900-2 and910-2 when the wave condition of the base station BS1 110-1 is bad. Thesignal selected by the DHT 210 is output to the destination through theswitch 207 and the line IF 206 or 208. More specifically, when thedestination is in the same mobile communication network 400, theselected signal is output to the base station 110 of the destinationthrough the line IF 206. Otherwise, the selected signal 930-2 (FIG. 1)is output to the communication network 150 (FIG. 1) through the line IF208. The DHT 210 may synthesize plural received signals as required.

The DHT 210 stores the selection result (the base station 110 that theselected signal comes from) in the memory 202 or storage device 203 ascall information such that the information can be used as informationfor selecting the base station for software upgrading in the basestation 110, which will be described later. Alternatively, a paththrough the line IF 206 or a path through the network managing apparatus250 in the I/O 204 may be used to notify the selection result to thebase stations 110 having sent the signals and/or the network managingapparatus 250. Then, the selection information may be stored as callinformation in the memory 112/252 or the storage device 113/253 of thebase stations 110 and/or the network managing apparatus 250.

The call information stored in the memory 202 or storage device 203 maybe created and be stored based on the control signal for call settingand/or disconnection actually exchanged between the base station 110 andthe base station control portion 200. In this case, since the basestation 110 itself can manage the call state, the selection result (callinformation) from the base station control portion 200 does not have tobe notified to the base stations 110.

FIG. 4 is a block diagram showing a construction example of the networkmanagement device. The network management apparatus 250 has aconstruction mentioned below. The network management device 250communicates with and controls the base stations 110 and/or the basestation control portion 200 through the control signal communicationpath 600.

The network management device 250 manages the maintenance and operationsof the entire wireless communication network 10 including plural mobilecommunication networks 400 each including plural base stations 110. Modespecifically, the network management device 250 includes, for example,plural I/O 254, a CPU 251, a memory 252, a storage device 253, akeyboard 256 and a monitor 257. These are connected in an internal bus255.

The I/O 254 is a communication interface for the base stations 110and/or base station control portion 200 in the wireless communicationnetwork 10. The CPU 251 controls the entire network managing apparatus250 and exchanges control signals (such as command signals) and/or datathrough the I/O 254 and also maintains and operates the entire mobilecommunication network 400 including the base station 110.

The memory 252 stores operational programs, for example, of the CPU 251.The storage device 253 stores data (such as information on terminals andbase stations) required for operating the wireless communication network10 in the network management device 250 and stores software and/orfirmware newly upgraded in the base stations 110. The keyboard 256 is aninput unit for inputting instructions from an operator (such as amaintenance staff). The monitor 257 is a display unit for notifying theoperator of the operation state of the wireless communication network10.

After the software and/or firmware to be upgraded online are stored inthe storage device 253 in accordance with the instruction from theoperator, for example, the online upgrading in the base stations 110 aresupported by following steps mentioned below.

FIG. 5 is a block diagram showing a construction and operational exampleof a wireless communication network where the transmission waves of thebase stations BS1 110-1 and BS8 110-8 are lower than those in FIG. 1. InFIG. 1, the cellular 100-1 of the base station BS 1 110-1 overlaps withthe cellars 100-2 to 100-7 of the adjacent base stations BS2 110-2 toBS7 110-7. On the other hand, in the state as shown in FIG. 5, thecellar 100-1 is reduced due to the decrease in transmission wave of thebase station BS1 110-1 and does not overlap with the other cellars.Similarly, the cellular 100-8 of the base station BS8 110-8 does notoverlap with the cellulars 100-2 and 100-3 of the base stations BS2110-2 and BS3 110-3.

Thus, the terminal MS1 300-1 cannot set the communication path 900-2with the base station BS1 110-1 and only can set the communication pathwith the base station BS2 110-2. The terminal MS1 300-1 selects thecommunication path 900-2 having better communication quality in FIG. 1.However, the communication path 900-2 cannot be set under the conditionas shown in FIG. 5. Therefore, the communication path 910-2 is switchedfrom the communication path 900-2 by the DHT 210-2 of the base stationcontrol portion 200-1. Similarly, the communication path 900-1 isswitched to the communication path 910-1 for the terminal MS2. The basestation control portion 200-1 communicates with the destination terminalby using the signals 920-1 and 920-2 from the switched communicationpath.

By controlling the transmission waves of the base stations as describedabove, the communication path being supplying a communication servicescan be switched without blackouts from a specific base station to theadjacent base station. Then, the base station no longer provides thecommunication service. Under this condition, software upgrading isperformed, and the transmission waves are returned to the original stateafter the software upgrading. In this case, the base station in whichthe software will be upgraded is repeatedly selected in accordance witha predetermined rule, and the above-described processing is performed onthe selected base station. Thus, the software upgrading in base stationsin the wireless communication network can be implemented withoutblackouts of communication services.

FIG. 6 is an operational explanatory diagram for describing an exampleof a software upgrading operation in a base station. First of all, inaccordance with a predetermined rule, the network management device 250selects base stations in which software will be upgraded (grouping step7-1). A group of the base stations selected in the step 7-1 is calledbase station group 1 (800-1). The details of the base station selectionwill be described later. When the network management device 250 requests(step 7-2) for transferring software to the base station group 1, thebase stations belonging to the base station group 1 (800-1) obtain (step7-3) new software from the network management device 250 and sendsacknowledgement of transferring software to the network managementdevice 250 (step 7-4). The network management device 250 forbids (step7-5) the base stations (800-x) other than those in the base stationgroup 1 (800-1) performing a service stopping operation (step 7-5) andsends a request for software upgrading to the base station group 1(800-1) (step 7-6). The step 7-5 may be omitted.

The base stations belonging to the base station group 1 (800-1)gradually decreases transmission power (step 7-7) when the request isreceived. Thus, calls connected to the base stations are handed over tothe neighbor base station sequentially. The base stations belonging tothe base station group 1 (800-1) checks if the base stations have nocalls (no communication path providing service) (step 7-9). Withreference to call information stored in the memory 112 or storage device113 or with reference to call information managed in the base stationcontrol portion 200, the base station can check if the base stationshave no calls. After determining no calls, the base stations are reset(step 7-10) and the base stations load new software (step 7-11). Thus,the base stations are restarted (step 7-12). The base stations belongingto the base station group 1 (800-1) gradually increase transmissionpower of the base stations (step 7-13) and acknowledge the completion ofthe software upgrading to the network management device 250 (step 7-14)when the transmission power reaches the original transmission power.

After the network management device 250 receives the acknowledgement ofthe completion of the software upgrading from all of the base stationsbelonging to the base station group 1 (800-1), the network managementdevice 250 selects new base stations in which software will be upgraded(step 7-15: grouping). A group of the selected base stations is calledbase station group 2 (800-2). The network management device 250 requeststhe transfer of software to the base station group 2 (800-2) (step7-16). The step 7-16 is the same as the step 7-2. The network managementdevice 250 performs the same processing on the base station group 2(800-2) as the processing at the steps 7-2 to 7-14 on the base stationgroup 1 (800-1). These steps are repeated until all of the base stationsare grouped. Thus, software upgrading can be performed in all of thebase stations.

In order to switch a call communication path in service connected to thebase station in which software will be upgraded to a neighbor basestation, software should not be upgraded in the neighbor base station atthe same time. Therefore, a predetermined rule is required for selectinga base station in which software will be upgraded.

FIG. 7 is an operational flow diagram showing an example of an operationin the network management device for selecting a base station in whichsoftware will be upgraded. The flow shown in FIG. 7 is a detail flow ofthe steps 7-1 and 7-15 in FIG. 6. Through the processing shown in FIG.7, the network management device 250 selects and creates base stationgroup n (where n is an integer of one or above).

First of all, the network management device 250 reads the number of callconnections from the memory 252 (step 8-1). Here, the network managementdevice 250 may read the number of call connections from the base stationcontrol portion 200 or each of the base stations 110. Next, the networkmanagement device 250 selects (step 8-2), as candidates for the basestation group n, the base station which has not belonged to any groupsyet and the base station which has not been excluded at steps 8-4 and8-8. Then, the network management device 250 selects from the candidatesthe base station having the least number of calls or the base stationhaving the fewer number of call connections than a predetermined numberof call connections. The selected base station is named as base stationA (step 8-3).

Next, if the number of call connections of the base station A is morethan the predetermined value, the network management apparatus 250excludes the selected base station from the candidates (step 8-4). Onthe other hand, if not, the network management device 250 add the basestation A into the base station group n (step 8-6). Then, the networkmanagement device 250 obtains information on the neighbor base stationsof the base station A from the memory 252 (step 8-7). The neighbor basestations of the base station A are excluded from the candidates for thebase station group n (step 8-8). When the base selected base station isexcluded from the candidates at the step 8-4, the steps 8-6 to 8-8 arenot necessary.

After that, the network management device 250 checks if any basestations to be candidates for the base station group n remain (step8-9). If the base stations to be the candidates still remain, theprocessing returns to the step 8-2. Then, the step 8-2 and subsequentsteps are performed. On the other hand, no base stations to be thecandidates remain, the network management device 250 ends the creationand selection of the base station group n (8-10).

By performing the above-described steps, software upgrading is notperformed in the base stations adjacent to each other at the same time.Therefore, the communication path of the call in communication servicein the base station in which software will be upgraded can be switchedto the neighbor base station.

FIGS. 8, 9, 10, 11 and 12 are explanatory diagrams for describing statesof the base station selecting operation shown in FIG. 7. The memory 252of the network management device 250 stores a table containing basestation identifiers, a number of calls connected to base stations(number of call connections), neighbor base station identifiers andgroup information, as shown in FIGS. 8, 9, 10, 11 and 12. By performingthe processing shown in FIG. 7 with reference to the table, a basestation group in which software will be simultaneously upgraded can beselected. The base station selecting operation will be described belowwith reference to FIGS. 8, 9, 10, 11 and 12.

FIG. 8 is a diagram showing a state before the selection of the basestation group. First of all, the creation of the base station group 1will be described. “0” in the column, “GROUP”, in the figures indicatesthat the base station does not belong to any group, meaning that thebase station can be the candidate for the selection. The networkmanagement device 250 selects a base station 1 having five callconnections, which is the least number of call connections, (or basestation 1 having fewer call connections than a predetermined callconnections (15 call connections, in this case) and identified first) byperforming steps 8-1 to 8-6 in accordance with the selecting processingin FIG. 7. Then, the network management device 250 gives “1” in thecolumn, “GROUP”.

Next, at steps 8-7 and 8-8 in FIG. 7, the number of the neighbor basestation of the base station 1 is referred, and “x” is given to thecolumn, “GROUP”, for the neighbor base station of the base station 1.Here, “x” indicates that the base station is excluded from thecandidates for the selection.

FIG. 9 shows the state at that time.

Furthermore, at a step 8-9 in FIG. 7, the network management device 250performs again the operation for selecting base stations at the step 8-2and subsequent steps since the base stations which can be the candidatesstill remain.

The network management device 250 selects a base station 21 having sixcall connections, which is the least number of call connections, (orbase station 21 having fewer call connections than the predeterminedcall connections (15 call connections, in this case) and identifiedfirst) from the base stations having “0” in the column, “GROUP”, (orother than the base stations having “1” and “x”) (step 8-2 to 8-4).Then, the network management device 250 gives “1” in the column, “GROUP”(step 8-6) and refers to the neighbor base station 22 of the basestation 21 (step 8-7). Then, the network management device 250 gives “x”to the column, “GROUP”, of the base station 22 (step 8-8).

Furthermore, by performing a step 8-9 and the step 8-2 and subsequentsteps, the network management device 250 selects a base station 8 havingeleven call connections, which is the least number of call connections,(or base station 8 having fewer call connections than the predeterminedcall connections (15 call connections, for example) and identifiedfirst) from the base stations having “0” in the column, “GROUP”, (orother than the base stations having “1” and “x”). Then, the networkmanagement device 250 gives “1” in the column, “GROUP”, thereof. Byperforming this processing until the base stations not having “1” or “x”in the column, “GROUP” no longer exist. Thus, the base station group 1can be created and be selected. (After this, the processing goes to astep 8-10.)

FIG. 10 is a diagram where the election of the base station group 1ends. The network management device 250 performs processing for softwareupgrading on the base stations having “1” in the column, “GROUP”. Afterthe completion of the software upgrading of the base station group 1,the network management device 250 changes “x” in the column “GROUP” to“0”, for example, which is data indicating that the upgrading has beenperformed or indicating that the base station is a candidate for theselection. Then, the network management device 250 selects the basestation group 2 in the same manner as the one described above. In thisexample, “0” stored in the column, GROUP” indicates that software hasnot been upgraded while a group number such as “1” indicates that thesoftware has been upgraded.

FIG. 11 is a diagram where the selection for the base station group 2has completed. Also in FIG. 11, the network management device 250selects base stations in the same manner as the selection for the basestation group 1 in FIG. 10 and gives “2” or “x” in the column, “GROUP”.In the case shown in FIG. 11, the base stations 5, 22, 7 and 3 aresequentially selected for the group 2 in accordance with the selectionoperation shown in FIG. 7 (where the base station having the least callconnections is selected).

The number of calls connecting to base stations are different betweenFIG. 10 and FIG. 11. This means that the call movement changes thenumber connecting calls because since there is a difference in timebetween the software upgrading for the base station group 1 and thesoftware upgrading for the base station group 2. According to thisembodiment, in order to prevent the change in the number of callconnection to be referred during the selection of a base station group,the number of call connections is read during the selection processing,and the selection processing is performed with reference to the readnumber of call connections. The number of call connections to bereferred is not limited to the read number of call connections, and theselection processing may be performed with reference to the changingnumber of call connections.

FIG. 12 is a diagram where the selection of a base station group 3 hasbeen completed. Also in FIG. 12, the network management device 250selects base stations and gives the group number “3” or “x” thereto inthe same manner as the selection of the base station groups 1 and 2 inFIGS. 10 and 11. In the case in FIG. 12, base stations 6, 4 and 2 aresequentially selected for the base station group 3 in accordance withthe selection operation shown in FIG. 7 (where the base station havingthe least number of connections is selected). As shown in FIG. 12, whenno base stations having “x” exist when the group selection completes,the group number is given to all base stations. This means that thecreation of the base station group has completed.

FIG. 13 is an operational explanatory diagram showing an operationalexample of transmission power reducing processing in a base stationwhere software will be upgraded. The operational example in FIG. 13 isdetail processing of the step 7-7 shown in FIG. 6. In the base station110 where software will be upgraded, the CPU 111 starts reducingtransmission power (step 12-1) in response to a software upgradingrequest from the network management device 250. The CPU 111 requests thewireless IF 116 to reduce transmission power by a predetermined amountof the power reduction rate (step 12-2). The wireless IF 116 reduces thetransmission power in response to the request (step 12-3) and notifiesthe CPU 111 of the transmission power value after the transmission powerreduction (step 12-4). The CPU 111 checks if the power value notifiedfrom the wireless IF 116 is the lowest value of the predeterminedtransmission power or not (step 12-5). If not, the processing returns tothe step 12-2, and the step 12-2 and subsequent steps are performedagain. On the other hand, if the notified power value reaches the lowestvalue, the CPU 111 ends the transmission power reduction (step 12-6).

Through these steps, the base station 110 can gradually reduce thetransmission power of the base station 110 and switch the communicationpath that the base station 110 is providing a communication service tothe neighbor base station. Thus, the state that the base station 110 nolonger provides the communication service can be obtained.

Next, another wireless communication network according to thisembodiment will be described below.

FIG. 14 is a block diagram showing a construction example of a wirelesscommunication network according to this embodiment. A wirelesscommunication network 10′ has a construction described below andimplements communication among terminals.

Plural mobile terminals MS1 300-1 and MS2 300-2 and plural wirelesscommunication apparatus (called base station hereinafter) BS1 110′-1 toBS8 110′-8 are connected by a wireless communication path, not shown.More specifically, each base station BS communicates with a terminal MSby using a CDMA in an area (called sector) that radio waves can reach.In the example in FIG. 14, a sector α 130-1, a sector β 130-2 and asector γ 130-3 are shown. However, each base station can have any numberof sectors. Though not shown, the sectors of each actual base stationoverlap and the sector α 130-1 and a sector γ 130-3 of the base stationBS1 can be set through communication paths 900-2 and 910-2 from theterminal MS1 300-1. In the following description for this embodiment, anarea where the plural base stations BS1 110′-1 to BS2 100′-8 cancommunicate with a terminal MS is called mobile communication network400′.

The base stations BS1 110′-1 to BS8 110′-8 of a mobile communicationnetwork 400′-1 are connected by a base station control portion (controldevice) 200-1 and a main signal communication path 500-1. The basestation control portion 200 includes a diversity handover unit (DHT) 210(which will be described in detail later) for performing soft handoverprovided in “3GPP TR25.832, Section 5.2.1”, for example. The basestation control portion 200 selects and communicates with onecommunication path having good communication quality from the pluralcommunication paths 900 and 910.

When the destination from the terminal MS1 300-1 is in the same mobilecommunication network 400′-1, the base station control portion 200-1returns a signal 930 selected by the DHT 210 to one of the base stationsBS1 110′-1 to BS8 110′-8 controlled by the base station control portion200-1 and communicates with the destination terminal MS. On the otherhand, the destination is a terminal of another mobile communicationnetwork 400′-2 (the detail construction of which is substantially thesame as that of the mobile communication network 400′-1 and will beomitted here), the base station control portion 200-1 exchanges signalswith the destination terminal through the communication network 150connecting between base station control portions 200 by using a basestation control portion 200-2 and a mobile communication network 400′-2.The communication network 150 may be a public network, an exclusive linenetwork and a private network. The mobile communication network 400′-2may be a so-called fixed network including a wired communication networkand terminals fixed in the wired communication network.

The network management device 250 is connected with the base station BS110′ and the base station control portions 200 in the communicationnetwork 10′ through a control signal communication path 600. The controlsignal communication path 600 exchanges control signals for monitoringand maintenance. For example, the network management device 250 managesand controls the entire facility of the communication network 10′ byupgrading software in the base station 110′. The number of sectorswithin the base station BS 110′, base station control portion 200,network managing device 250, and each base station BS is not limited tothe number shown in FIG. 14 but may be any number.

FIG. 15 is a block diagram showing a construction example of a basestation in a communication network. The base station 110′ has aconstruction mentioned below. The base station connects betweenterminals and the base station control portion and communicates with thenetwork managing device.

When the base station 110′ receives, at an antenna 119′-1, a signal(wave signal) from the terminal MS 300 through a wireless communicationpath, not shown, a wireless IF unit 116-1 performs terminationprocessing such as the conversion of the wave signal to an electricsignal. A communication processing unit 117-1 performs processing (suchas communication processing for call controls) on the signal after thetermination processing in order to perform various communicationservices. A line IF unit 118 matches the interface with the base stationcontrol portion 200. Then, the signal is sent to the base stationcontrol portion 200 through a main signal communication path 500. Thebase station 110′ sends the signal from the base station control portion200 to the terminal MS 300 by following steps in the opposite directionof the above-described processing. This is a case where the sector αcontrol portion 120-1 exchanges signals (wave signals). However, theexchanges of signals (wave signals) by the sector β control portion120-2 and sector γ control portion 120-3 can be performed in the samemanner.

The CPU 111-4 of an apparatus management portion 121 of the base station110′ uses a control program stored in the memory 112-4 and data (such asinformation on terminals) required for operating the wirelesscommunication network 10′. In this case, the data is stored in a storagedevice 113. Thus, the CPU 111-4 controls the entire base station 110′such as the sector control portions 120-1 to 120-3 and the line IF 118.

The CPU 111-1 to 111-3 of the sector control portion 120-1 to 120-3 ofthe base station 110′ uses a control program stored in memories 112-1 to112-3 to control the wireless IF units 116-1 to 116-3 of the sectors andcommunication processors 117-1 to 117-3 of the sectors in response to aninstruction from the apparatus management portion 121.

These units are connected through an internal bus 115. An I/O 114connected to the internal bus 115 is an interface with the networkmanaging device 250 and exchanges, through a control signalcommunication path 600, a control signal (or command signal) and variouskinds of data required for control of the operation and maintenance ofthe communication network 10′. Here, the I/O 114 may be removed and themain signal communication path 500 may be used to add these controlsignal and data to the signals exchanged through the main signalcommunication path 500. Then, the resulting signals may be exchangedthrough a line IF unit 118.

In the base station 110′, upon the upgrading of communication servicesprovided in the wireless communication network 10′, the CPU 111-4 of theapparatus management portion 121 upgrades software (such as a controlprogram) stored in the memories 112-1 to 112-4 of the apparatusmanagement portion 121 and the sector control portions 120-1 to 120-3 orfirmware (such as a control program) stored in the wireless IF units116-1 to 116-3, communication processing units 117-1 to 117-3 and lineIF unit 118 by following steps and performing operations mentioned belowand by keeping the base station in use (in operation or at on-linestate). The operation for upgrading software and/or firmware while thebase station is being used may be called on-line upgrading hereinafter.

FIG. 16 is a block diagram showing a construction and operationalexample of a wireless communication network where the transmission waveoutput of the sector α 120-1 of the base stations BS1 110′-1 to BS8110′-8 is lower than the one in FIG. 14. While the sector α 120-1 of thebase stations BS1 110′-1 covers the area having a terminal MS1 300-1 inFIG. 14, the area covered by the sector α 120-1 of the base stations BS1110′-1 is reduced since the output of the transmission wave of thesector α 120-1 of the base station is reduced in FIG. 16. Thus, the areahaving the MS1 300-1 cannot be covered. Then, similarly, the sector α ofthe BS8 110′-8 cannot cover the area having the terminal MS2 300-2.Therefore, the terminal MS 300-1 cannot set the communication path 900-2with the sector α of the base stations BS1 110′-1 and can only set thecommunication path with the sector γ of the base stations BS1 110′-1.While the terminal MS1 300-1 selects the communication path 900-2 havinggood communication quality in FIG. 14, the communication path 900-2cannot be set in FIG. 16. Therefore, the communication path is switchedto the communication path 910-2 by the DHT 210-2 of the base stationcontrol portion 200-1. For the same reason, the communication path 900-1is switched to the communication path 910-1 for the terminal MS2. Thebase station control portion 200-1 communicates with a destinationterminal by using signals 920-1 and 920-2 from the switchedcommunication paths.

By controlling the transmission waves of base stations, thecommunication paths being providing communication services can beswitched without blackouts from specific sectors of the base stations.Then, the base station no longer provides the communication service.Under this condition, the processing for software upgrading andreturning the transmission waves to the original state after thesoftware upgrading is performed sequentially on the base stations andthe plural sectors (α, β and γ) control portions. Thus, software in thebase stations in the wireless communication network can be upgradedwithout the blackouts of communication services.

FIG. 17 is an operational explanatory diagram describing an example of asoftware upgrading operation in a base station. The network managementdevice 250 performs software-transfer instructing processing on basestations (step 17-1). Each of the base stations obtains new software byperforming processing for obtaining new software (step 17-2) andnotifies the network management device 250 on the completion of thesoftware transfer (step 17-3). Next, the network management device 250instructs each of the base stations to upgrade software (step 17-4). Thesoftware upgrading processing (step 17-5) for the sector α controlportion, software upgrading processing (step 17-6) for the sector βcontrol portion and software upgrading processing (step 17-7) for thesector γ control portion are performed sequentially. After the end ofthe software upgrading processing for the device control portion (step17-8), the end of the software upgrading is notified to the networkmanagement device (step 17-9). FIG. 18 shows details of the softwareupgrading processing (steps 17-5 to 17-7) for the sector controlportions. FIG. 19 shows further details thereof. FIG. 20 shows detailsof the software upgrading processing (step 17-9) for the device controlportion.

FIG. 18 is an operational flow diagram describing details of thesoftware upgrading processing (steps 17-5 to 17-7) for the sectorcontrol portions. First of all, the device control portion 121 performsprocessing for requesting the reduction of transmission power on thesector X (where X is α, β or γ) control portion 120 (step 18-1). Thesector X control portion 120 gradually reduces the transmission power(step 18-2). Thus, the call being processed by the sector X is handedover to the neighbor sector, and the communication service for the callis kept. When the transmission power reducing processing has completed,the sector X control portion 120 notifies the apparatus control portion121 of the completion (step 18-3). The apparatus control portion 121checks whether no calls are connecting to the sector X or not (step18-4). After that, the apparatus control portion 121 requests thesoftware upgrading for the sector X control portion 120 to the sector Xcontrol portion 120 (step 18-5). In response to the request for thesoftware upgrading request, the sector X control portion 120 resets thesector X control portion 120 (step 18-6). Thus, the sector X controlportion 120 loads new software (step 18-7). After that, the sector Xcontrol portion 120 restarts the sector X (step 18-8) and graduallyincreases the transmission power of the sector X (step 18-9). Thus, thecommunication processing by the sector X can be implemented again. Uponthe completion of the processing for gradually increasing thetransmission power of the sector X (step 18-9), the sector X controlportion 120 notifies the apparatus control portion 121 of the completionof the software upgrading (18-10). In order to hand over the call to theneighbor sector, the processing in FIG. 18 is not performed on thesector (α, β and γ) control portions at the same time and issequentially performed thereto as shown in the software upgradingprocessing (steps 17-5 to 17-7) for the sector control portions in FIG.17.

FIG. 19 is an operational flow diagram describing the step for graduallyreducing the transmission power (step 18-2) shown in FIG. 18. Inresponse to the request for reducing the transmission power from the CPU111-4 of the device control portion (step 18-1), the CPU 111-1 111-2 or111-3 of the sector X control portion 120 starts reducing thetransmission power (step 19-1). The CPU 111-1 111-2 or 111-3 requeststhe wireless IF 116-1 116-2 or 116-3 to reduce the transmission power bya predetermined rate of the power reduction (step 19-2). In response tothe request, the wireless IF 116-1 116-2 or 116-3 reduces thetransmission power (step 19-3). Then, the transmission power value afterthe transmission power reduction is notified to the CPUs (111-1 to111-3). The CPU 111-1 111-2 or 111-3 checks if the power value notifiedfrom the wireless IF 116-1 116-2 or 116-3 is the lowest value of thetransmission power or not (step 19-5). If not, the step 19-2 isperformed again. If the notified power value reaches the lowest value,the completion of the reduction of the transmission power is notified(step 18-3).

Through these steps, a base station can gradually reduce thetransmission power of the sector within the base station. Then, thecommunication path providing a communication service to the sectorwithin the base station can be switched to the neighbor sector. Then,the state that the communication service is no longer provided to thesector within the base station can be achieved, and software can beupgraded.

FIG. 20 is an operational flow diagram describing details of thesoftware upgrading step (step 17-9) by the apparatus control portion 121within the base station in FIG. 17. The apparatus control portion 121loads new software (step 20-2) by resetting the apparatus controlportion 121 (step 20-1). Then, the apparatus control portion 121 isrestarted (step 20-3). Since the reset of the apparatus control portion121 does not affect on the main signal communication path 500, thecommunication service can be maintained even during the softwareupgrading by the apparatus control portion 121.

According to the invention, a wireless communication apparatus, awireless communication network and a software upgrading method can beprovided which can upgrade software in the wireless communicationapparatus within the wireless communication network even while thewireless communicating network is providing various communicationservices. Furthermore, according to the invention, a wirelesscommunication apparatus, a wireless communication network and a softwareupgrading method can be provided which can upgrade software withoutblackouts of communication services being provided. Furthermore,according to the invention, these apparatus and method can be achievedwith simple and economical constructions and steps.

1. A base station apparatus for communicating with a wireless terminaland a wired communication network within a wireless communicationnetwork which is capable of soft handover, the base station apparatuscomprising: a wireless interface for communicating with the wirelessterminal; a wired interface for communicating with the wiredcommunication network; a communication processing portion for performingprocessing for providing communication services to the wireless terminalthrough the wireless interface and the wired interface; and a controlportion for controlling the base station apparatus, wherein, the basestation apparatus has a first operation mode and a second operation modeat the time of updating software of base station apparatuses in thewireless communication network, wherein in the first operation mode,when the control portion receives a control signal to prohibitperforming a service stopping operation from a network management devicewhich transmits and receives control signals for operation ormaintenance of the wireless communication network, the control portioncontrols the wireless interface, the wired interface and thecommunication processing portion so as not to perform the servicestopping operation, and wherein in the second operation mode, when thecontrol portion receives an upgrading request which is transmitted fromthe network management device to the base station apparatuses in whichsoftware will be upgraded, the control portion reduces output power ofthe transmission wave of the wireless interface, after determining thatno calls are connected to the base station apparatus or a sector of thebase station apparatus, upgrades software set therein to softwarereceived through the wired interface in advance, and returns the outputpower of transmission wave of the wireless interface to its originalstate after the software has been upgraded.
 2. The base stationapparatus according to claim 1, wherein the control portion graduallyreduces the output power of the transmission wave of the wirelessinterface to a predetermined lowest value.
 3. The base station apparatusaccording to claim 1, wherein the control portion, after the softwarehas been upgraded, gradually increases the output power of thetransmission wave of the wireless interface.